In wireless network systems, a wireless client device can detect nearby access points by broadcasting a probe request, and listening for probe responses from any access points that hear the probe request. The probe responses will typically include information about the responding access point and the wireless network to which the access point provides service. The probe response may include information such as a transmitter address of the access point, a destination address of the client device that sent the probe request, a retry flag, the Service Set Identifier (SSID) of the wireless network, supported data rates, as well as other information about the access point.